Trusted communications between untrusting parties

ABSTRACT

A system and method is disclosed for assuring that networked communications between parties playing a game on a network (e.g., the Internet) are not tampered with by either of the parties for illicitly gaining an advantage over the other party. An initial sequence of tokens (e.g., card representations) for playing the game are doubly encrypted using an encryption key from each of the parties. Accordingly, during play of the game neither party can modify the initial sequence of game tokens during the game. At termination of the game, at least one of the parties can fully decrypt the initial sequence of tokens, and thereby, if desired, compare the played token sequence with the corresponding the initial token sequence.

The present application is a continuation of U.S. patent applicationSer. No. 11/147,501 filed Jun. 6, 2005 which is a continuation of U.S.patent application Ser. No. 09/617,386, filed Jul. 17, 2000 which claimsthe benefit of U.S. Provisional Patent Application No. 60/144,350, filedJul. 16, 1999, the entire disclosure of each of these applications isherein incorporated by reference.

RELATED FIELD OF THE INVENTION

The present invention is related to assuring each of a plurality ofparties, e.g., communicating on a network that none of parties canillicitly manipulate the information being communicated; however, aftera predetermined event, e.g., the termination of a game, the informationcan be viewed and verified by all parties.

BACKGROUND OF THE INVENTION

Electronic communications and interactions such as on networks like theInternet have greatly expanded the potential for interactions amongpeople, organizations and businesses. However, although suchcommunications offer substantial advantages in terms of the speed andease of communications, these advantages are often offset by thedisembodied nature of the communications. In particular, electronicnetwork communications between parties wherein at least one of theparties is believed to be potentially untrustworthy, or there is aquestion about one of the parties' authenticity can greatly affect theacceptance of electronic communications as a substitute for face-to-facecommunication. Accordingly, when communicating particularly sensitiveinformation between two parties, it would be preferable that each partybe able to verify that the sensitive information is treated as intended.For example, when games are played on the Internet wherein such gamesoffer prizes and/or returns on bets, and where the games are largelydependent upon a predetermined order or arrangement of tokens (e.g.,card representations) or game scenarios, network game players may findit difficult to fully trust the game sponsor/provider to not distort thechances of game players to receive all prizes and/or be fairlycompensated for wagers made. Alternatively, such game sponsors/providersare unwilling to provide to game players the game outcomes prior to thecompletion of such a game in that the game players could potentially usesuch outcomes prior to the completion of the game for their own benefit.Thus, it would be desirable to have a communications network capabilitythat guarantees that both network game players, and sponsors/providersof games (such as contests, sweepstakes, and casino games), each to beable to verify that the other party is playing the game fairly.

Alternatively, when providing an auction for electronic sealed bids,similar concerns regarding trustworthiness of auction parties mayundesirably affect the bidding process. For instance, when a pluralityof companies are competing with one another for a contract, there may bea concern that a sealed bid from one company might be inappropriatelycommunicated to another of the bidding companies. Thus, it would bedesirable for such companies to be assured that their sealed bids couldnot be misappropriated by competing companies.

SUMMARY OF THE INVENTION

In one aspect, the present invention is a novel method and system forassuring that no party involved in the play of a game is able to ainappropriately tamper with or inappropriately disclose pre-gamearrangement of tokens and/or events for the game. More generally, thepresent invention reduces the likelihood that any of the partiesinvolved in a game or contest (e.g., parties such as thesponsor/provider of a game or contest, or any player of the game orcontest) is likely to play unfairly by unscrupulously manipulating ordisclosing the arrangement of tokens and/or events of the game orcontest. The present invention is particularly useful in assuring suchparties when game or contest communications between parties occur viatransmissions on a communications network such as a local are network, awide area network, the World Wide Web, the Internet, or some combinationof the above.

In one embodiment of the present invention, at least one trusted thirdparty is utilized for assuring that both players and game sponsorsperceive the game as being played fairly. For example, when playing acard game on the Internet (or other communications network), whereinwagers are placed on a game outcome, such a trusted third party might bea website to which a representation of card deck(s) for playing the gameis transmitted by the sponsor/provider prior to commencement of thegame, and wherein, e.g., the copy of the card deck(s) at the trustedthird party is available to the game players upon completion of the gamefor checking against the cards actually played in the game. Accordingly,the game sponsor/provider may provide to each game player, prior to agame commencement, an identification tag for identifying the deck(s)with which the player is playing so that upon termination of the gamethe player can present (e.g., transmit via the network) the tag to thetrusted third party for thereby receiving a copy of the deck(s)representation. That is, once the game is completed and thesponsor/provider has notified the trusted third party that the game iscompleted, each player would be able to receive a copy of the deck(s)from the third party by providing the identification tag.

Alternatively, such a card deck(s) representation may be generated bythe trusted third party and subsequently provided to the gamesponsor/provider along with an identification tag for identifying thedeck(s) so that the sponsor/provider can, in turn, provide theidentification tag to game players using the deck(s) when playing agame. Subsequently, upon game termination, each player may request fromthe trusted third party, a copy of the deck(s) representation used inplaying the game. In another embodiment, each player may transmit a gamelog to the trusted third party, wherein the third party performs acomparison between the card representations played and the correspondingcard representations in the copy of the deck(s) representation retainedby the third party. Moreover, note that similar verification techniquesmay be used with other games or contests for assuring that pre-game orpre-contest data is not inappropriately changed during the game orcontest.

In another embodiment of the present invention, a trusted third party isunnecessary. Instead, the game sponsor/provider and the players transmitvarious encryption keys and encodings of the pre-game arrangements ofgame tokens and/or game events between one another according to a methodof the present invention that substantially assures that the pre-gamearrangement is neither tampered with during the game, nor known to agame player prior to an appropriate disclosure time during or after thegame. In particular, this embodiment of the present invention, whenapplied to a communications network version of a card game (such as onthe Internet), provides for the date representation of the card deck(s)to be encrypted using a first encryption key provided by a game player,and then encrypted using a second encryption technique provided by thegame sponsor/provider. More precisely, for each player, the presentinvention allows the representation of the card deck(s) for the game (orinstance thereof) to be doubly encrypted prior to commencement of thegame, and the doubly encrypted version of the deck(s) is provided to theplayer of the game prior to game commencement. Thus, upon termination ofthe game, each player may utilize a decryption key provided at gametermination by the game sponsor/provider to decrypt the secondencryption of the card deck(s), and subsequently use the player'spersonal decryption key to decrypt the first encryption of the carddeck(s). Accordingly, each game player may receive a substantiallydistinct doubly encrypted version of the card deck(s) prior tocommencement of a game instance, but the game player is unable todetermine the cards within the deck(s) other than by playing the gamesince the encrypted version of the deck(s) provided to the player isencrypted with at least one encryption technique wherein the decryptionkey is not provided to player until the game instance is completed.

In a general context, it is an aspect of the present invention that foran activity (such as a game or contest), wherein a predeterminedarrangement of tokens and/or events (e.g. a card deck) is pivotal to thesuccess of a user in performing (an instance of) the activity, thepresent invention also provides both the users (e.g., participants) andthe activity sponsor/provider with the assurance that the predeterminedarrangement is unlikely to be manipulated or disclosed so that one partyhas an unanticipated advantage or disadvantage. Thus, the likelihoodthat a user is at an unanticipated disadvantage is reduced. In oneembodiment of the present invention, the predetermined arrangement isdoubly encrypted substantially as described above, and the results areprovided to each user. Thus, the predetermined arrangement is firstencoded by the sponsor/provider, via a first encryption technique, usinga user supplied public key, and subsequently, the result is encoded sothat a secret key, not known by the user, is to be used in decoding thelatter encoding. Moreover, note that the order of applying the first andsecond encryption techniques may be reversed in some embodiments.Additionally, to further assure that the predetermined arrangement doesnot place a user at an unanticipated disadvantage, the present inventionallows a user to select tokens or events in an order different from thepredetermined arrangement. For example, when the activity is a game,such game tokens (e.g., cards) or game events may be selected by a userindicating the position of a desired game token relative to other tokensor game event representations in the predetermined arrangement. Forinstance, if the game uses a deck of cards, a user may choose to playonly every other card, or more generally, every n^(th) card (n≥2).Alternatively, other characteristics of such tokens or eventssubstantially unrelated to their game utilization may be used forselection; e.g., a color, size, or shape of such a token and/or eventrepresentation may be used.

Note that for parties utilizing a network for communications, the doublyencoded aspect of the present invention together with the ability ofusers to select from among a predetermined arrangement of tokens orevents according to a user desired selection criteria, is analogous tothe technique for assuring fairness in a face-to-face card game whereinone participant of the game shuffles and another participant cuts thecard deck.

Accordingly, the present invention can be utilized for substantiallyassuring the integrity of parties' actions during network communicationsfor:

(a) Games utilizing dice (e.g. board games, craps, etc.), or cards,(e.g., poker, blackjack, hearts, etc.);

(b) Games wherein objects must be located and/or a particular path mustbe identified and traversed (e.g., electronic treasure hunt games wherethere is a predetermined one or more winning game configurations withina simulated or virtual environment);

(c) Network lotteries or drawings, wherein the winning gameconfigurations are predetermined prior to commencement of the game;

(d) Selection games such as games where a game player selects one ormore game tokens and/or game events, and wherein for at least some ofthe potential game selections, there is a predetermined prize associatedtherewith. For example, Internet games wherein a graphic is displayed toa game player and the player is able to select a location on the graphicfor determining if the location selected (e.g., a pixel) has a prizeassociated therewith; and

(e) Electronic versions of sweepstakes contests wherein contestants areprovided with a contestant identification such that if theidentification has been selected as a winning identification, thecontestant wins a particular prize;

(f) Testing services wherein testing is performed via a communicationsnetwork;

(g) Auctions via a communications network, wherein, e.g., bidders may bewary of the security of their bids in a sealed bid auction.

Other benefits and features of the present invention will become evidentfrom the detailed description and accompanying drawings herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flowchart of a first embodiment of the present invention forassuring trusted communications regarding a contest provided on acommunications network.

FIG. 2 is a flowchart of a second embodiment of the present inventionfor assuring trusted network communications among potentiallyinteresting parties involved in an activity such as same or contest.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 illustrates a first embodiment of the present invention whereinthe users of a communications network are able to enter contests (e.g.,lotteries, sweepstakes, drawings, etc.) on the network and be assuredthat a predetermined winning entry to the contest cannot be manipulatedduring the contest. Thus, the present invention provides greater trustby contestants in the contest sponsor/provider since there is assurancethat one or more winning entries have already been selected and thatanyone who selects such a winning entry will indeed win the contest.

Moreover, note that the network for the contest can be the Internet, theWorld Wide Web, a wide area network, or a local area network such as maybe provided in a casino, hotel, cruise ship or aircraft. Accordingly,the flowchart of FIG. 1 may be described as follows. In step 104, eachuser (e.g., contestant) generates a public/private encryption key pairsuch as is well known in the encryption arts. For example, variousversions of the procedure known as RSA can be used to generate thepublic/private encryption key pair. One such commercially availablesoftware product enabling RSA is the product PGP (also known as “PrettyGood Privacy”) that is widely available.

Subsequently, in step 108, each user provides his/her public encryptionkey (generated in step 104) to a network site (e.g., an Internetwebsite) that is providing the contest. For example, such publicencryption keys may be provided with a user's identification (e.g.,password) for registering at the network site. Subsequently, in step112, the network site determines the one or more winning contestentries. Note that the winning entries may be determined at any timeprior to the commencement of allowing users to enter the contest. Forexample, in providing an Internet lottery system, one or more winningsets of lottery numbers can be determined prior to allowing users toselect lottery number combinations, and according to the presentinvention, such users can be assured that the winning lotterycombinations have not been tampered with between their selection and thecompletion of the lottery.

Subsequently, as each user, U, enters the contest (step 116), thepredetermined winning entries are encrypted with the user's publicencryption key obtaining a result denoted herein as“USER_ENCODED_WINNERS(U)”. Thus, as one skilled in the art willunderstand, the contest sponsor/provider thereafter is substantiallyunable to tamper with such encoded winning entries. As an aside, it isworth noting that users may enter such a contest in other ways besidestransmitting network (e.g., Internet) contest entry requests. Inparticular, such requests may also be provided via e-mail, a voicetelephone call, or conventional mail.

In step 120, the network site subsequently generates one or more privateencryption keys Note that such keys need not be generated specificallyaccording to the sequence of steps provided in FIG. 1. In particular,such private encryption keys K_(i) may be generated by the network siteat substantially any time prior to step 124 described hereinbelow.Accordingly, in step 124, the network site encrypts eachUSER_ENCODED_WINNERS(U) using one of the network site private keysK_(i), thereby obtaining a result denoted herein as“DOUBLY_ENCODED_WINNERS(U, K_(i))”. Note that such private (e.g.,equivalently, secret) keys K_(i) may be used with various types ofencryption procedures such as DES (U.S. government standard specified inFIPS PUB 46). However, other private/secret encryption techniques arealso within the scope of the present invention, such as IDEA™,Blowfish™, RC4™, RC2™, SAFER™, and various hashing techniques, as oneskilled in the art will understand. Further, public/private keyencryption techniques may also be used here if desired.

In step 128, each user U is provided with a corresponding doubly encodedversion of the predetermined winning contest entries,DOUBLY_ENCODED_WINNERS(U, K_(i)). Accordingly, although each user U hasa private key that is able to decode a message encoded with the user'spublic key, the user is unable to decode the transmission of the contestwinners without the corresponding private/secret encryption key K_(i).Further, note that although many encryption schemes can be broken ifthere is sufficient time and computational capacity, note that byproviding sufficiently long keys K_(i) (e.g., 128 bit keys or longer),such illicit decrypting by a user is reduced. Further, since theidentification of the one or more winning entries can be substantially astring of (e.g., ASCII) characters, with possibly additionalsubstantially random or “noise” character codes (more generally, datairrelevant to the identification of the winning entries) interspersedtherein for further security, it is believed that such doubly encodedversions of winning contest entries are secure from illicit decrypting.In particular, with the interspersing of noise character codes andassuming the winning entry data is sufficiently long (e.g., 12 to 20characters or longer), the length of the string to subsequently doublyencrypt (this string denoted herein “noisy winning entry data”) can besubstantially longer than the actual winning entry data. Moreover, aformula for identifying the actual winning entry data within the noisywinning entry data can be provided (after contest termination) to theuser. For instance, such formulas may be as simple as starting with thej^(th) character of the noisy winning entry data, select every other(alternatively, every n^(th) where n≥2) character to derive the winningentry data.

Once a user U has received his/her correspondingDOUBLY_ENCODED_WINNERS(U, K_(i)), the user may enter the contest one ormore times (step 132), wherein the user retains either electronically orotherwise the identification of each of his/her contest entries.Subsequently, in step 136, after all contest entries are received, thenetwork site transmits the appropriate network site private encryptionkey K_(i) to each user, optionally, together with a user readableversion of the winning entries. Accordingly, in step 140, each user isable to decrypt his/her doubly encoded version of the predeterminedwinning contest entries using first the private key K_(i) transmitted bythe network site together with, e.g., a standard decryption programprovided by, for instance, a commercially available decryption packageor by decryption software obtained (e.g., downloaded) from a trustedthird party network site (e.g., website). Subsequently, the user is thenable to decrypt the results from the above decryption process by usinghis/her private encryption key. Thus, a recognizable copy of the winningentries then becomes available to each user. Note, however, that ifwithin the data for the winning entries there was initially interleavedother noise characters (thereby obtaining noisy winning entry data),then a subsequent communication from the network site indicating, e.g.,which characters to use in determining the predetermined winning entriesmay also be provided to each user. For example, such additionaltransmissions may provide a simple formula for ultimately determiningthe characters of the winning entries from the doubly decrypted data.Subsequently, in step 144, each user is able to determine whether he/shehas a winning entry by comparing his/her contest entry identificationswith the winning identifications obtained from step 140.

It is important to note that if the noise characters are intersperseddifferently for each of a sufficiently large number of contest users,then the contest sponsor/provider will be unable to change thepredetermined winning entries during or after the contest by simplychanging the formulas prior to providing the formulas to the users.

Moreover, if the sponsor/provider publicizes the winning entries afterthe contest is terminated, and, for example, users are able tocommunicate with other users (e.g., via a bulletin board or network chatroom) and/or users are able to view a sufficiently large plurality ofdifferent instances of noisy winning entry data that were actuallyprovided to other users during the contest, then it is believed thatusers will be assured that no alternative set of one or more winningentries could have been substituted by the sponsor/provider changingformulas during the contest. Further, note that it is within the scopeof the present invention that the step of providing the noisy winningentry data can be accomplished in various ways, such as positioningcharacters of the winning entries according to: (a) at offsets fromprime number positions in a resulting noisy winning entry data instance,or (b) a geometric progression wherein the number of noise charactersbetween consecutive characters identifying the winning entries growsgeometrically (e.g., 2 noise characters, then 4 noise characters, then 8noise characters, etc.). It is, however, in at least one embodiment,preferable that each contest user be able to easily determine thewinning entry data from noise characters without relying upon anycomputational module provided by the sponsor/provider, and morepreferably, each user should be able to determine the winning entry datawithout any computational assistance whatsoever (i.e., entirelymanually).

Note that it is also within the scope of the present invention that thecontest sponsor/provider need not communicate with users entirely vianetwork communications from a network site as described hereinabove. Inparticular, contest communications may be also performed by traditionalmailings. Moreover, it is also within the scope of the present inventionthat contest processing need not necessarily be performed at the networksite as indicated in some steps of the flowchart of FIG. 1. Inparticular, the network site may merely provide a network portal tovarious contests wherein the contest processing is performed remotelyfrom the network site and transmitted therethrough to the contest users.Additionally, note that it is within the scope of the present inventionthat the phrase “each user” in the steps of FIG. 1 may be replaced withphrases such as “some one or more users”. For instance, it is within thescope of the present invention that the steps provided in FIG. 1 may beasynchronously performed for each user such that for different users,the different users and/or the network site may be substantiallysimultaneously performing different steps of the flowchart of FIG. 1.For example, a first user may be generating his/her public/privateencryption key pair (e.g., step 104), while a second user may besubstantially simultaneously in the process of providing a contest entry(e.g., step 132). However, in at least one embodiment of the presentinvention, the predetermining of winning entries (e.g., step 112) shouldoccur prior to the receipt of user contest entries (e.g., step 132) forat least a sufficient number of users so that substantially all userstrust that the predetermined contest winning entries were not illicitlymodified after users were allowed to enter the contest.

The flowchart of FIG. 2 illustrates another embodiment of the presentinvention for providing trusted communications between parties, whereinat least one of the parties may be inclined to distrust communicationsprovided by the other party. For instance, the flowchart of FIG. 2illustrates an embodiment of the present invention for use in providingtrusted network communications in activities such as various kinds ofgames and contests. In particular, the flowchart of FIG. 2 describessteps to be performed related to communications between two partieswherein a first of the parties provides an activity that can beperformed by a second party, and further, the first party selectivelyprovides the second party with data related to the activity, asappropriate, while the second party is performing the activity and/orafter the second party has completed the activity. Note that suchactivities may be:

-   -   (a) various interactive games such as card games (e.g., hearts,        poker, blackjack);    -   (b) contests (e.g., lotteries, sweepstakes, drawings, or other        games wherein users, such as players or participants, select or        receive contest entries);    -   (c) activities wherein prizes are distributed throughout a        simulated or virtual environment and wherein a user encounters        the prizes by a combination of skill and/or fortitudinous        selection (e.g., a simulated graphical maze-type video game such        as dungeons and dragons, a game wherein a user attempts to        select a “winning” simulated graphical door, selection of a        “winning” pixel of a displayed graphic, various combat games        wherein users encounter prizes on different levels of the game,        and treasure hunt-type games wherein a user searches through a        simulated environment for prizes encountered therein).

Accordingly, in all such activities, there is data related to theactivity which should not be manipulated by a sponsor/provider of theactivity to the detriment of a user, and correspondingly such datashould not be misused by the user to the detriment of the activitysponsor/provider and/or other users. For example, if one such activityis a networked representation of a card game, such as poker orblackjack, a sponsor/provider (or dealer) for the networked game maydetermine (as such activity related data) a card ordering for one ormore card deck representations to be used in playing the game. Moreover,it is typically assumed that the card representations in the card deckrepresentations should not be reordered or inappropriately manipulatedduring the game, and that game users (e.g., players) should only be ableto view the faces of card representations as is appropriate to the rulesof the game. As a further example, consider an interactive networkadvertisement (e.g., on the Internet), wherein the advertisementconsists of a virtual world having embedded therein advertisinginformation related to at least one of a product and a service as wellas prizes, bonuses, and/or discounts related to the products and/orservices being advertised. For instance, such a virtual world may allowa user to navigate through this world and accumulate various prizesaccording to the area of the world explored, and optionally, alsoaccording to the user's expertise in playing a game provided in thevirtual world, or the user's knowledge regarding some area of knowledgepossibly related to the products or services being advertised. Forexample, such a virtual world might include past, current and futurecars from a particular automaker wherein users are allowed to assemble,disassemble, redesign, drive and/or crash these cars, and wherein prizessuch as discounts for buying a car currently being manufactured by theautomaker are distributed throughout the virtual world). Thus, in such avirtual world, it would be desirable that users be assured that theprizes promoted as being contained therein are indeed eligible for theusers to acquire. Thus, one way to provide the user with such assurancesis provided in the flowchart of FIG. 2.

Moreover, note that the present invention may be used in interactiveadvertising such as is presented to Internet users. For instance, whensuch users are viewing and/or interacting with an Internet presentation(e.g., a search engine, an online personal finance system, or an onlineshopping system), advertisements may offer prizes (or othercompensation) for interacting with their advertisements, wherein theuser has a chance of winning a prize by entering a contest or playing agame such as attempting to select a winning pixel, or other graphicalarea. Accordingly, the present invention can be used to assure the userthat the prize winning area has already been determined.

The steps of FIG. 2 are described as follows: in step 204, a prizeoffering entity (e.g., an Internet website, or a casino having a gaminglocal area network) provides an activity wherein:

(a) It is possible for each user performing the activity (or an instancethereof) to obtain one of a plurality of outcomes, and

(b) Such outcomes determine the prizes and/or winnings offered to usersperforming the activity.

In step 208, the prize offering entity generates data related to (aninstance of) the activity being offered, wherein for convenience, thisdata is denoted ACTIVITY_DATA. Note that ACTIVITY_DATA is dependent uponthe type of activity provided by the prize offering entity. Thus, if theactivity offered is a card game, then ACTIVITY_DATA may be arepresentation of a card deck or card shoe. Alternatively, if theactivity is a contest, lottery or other similar endeavors, thenACTIVITY_DATA may be a predetermined association between:

-   -   (i) Possible winning user outcomes (e.g., winning entries        wherein the activity is a contest), and    -   (ii) Prizes to be awarded to the user(s) having the winning        outcomes.

Additionally, such ACTIVITY_DATA may be a predetermined sequence of dicerolls (e.g., a predetermined sequence of numbers between 2 and 12) foractivities such as games where the dice values determine the position ofa user's token (e.g., Monopoly-type games), or other games such as crapsor other wagering games dependent upon dice rolls. Further, suchACTIVITY_DATA may be related to activities such as games or simulationshaving predetermined stochastically generated controlling data and/orhaving probabilities regarding the encountering of prizes. For example,games such as network-based (e.g., Internet) slot machine simulationswhereby an advertised percentage of funds are received from the playingof such slot machines is returned as winnings. Thus, ACTIVITY_DATA mayinclude the slot machine results for, e.g., the next 500 plays. Thus,after a user indicates to the prize offering entity his/her desire tostop playing, the user would then be allowed to decrypt an encryptedversion of ACTIVITY_DATA to determine, e.g., what slot machine playswould have occurred if the user had continued, so that, e.g., the usermay determine how close to the advertised percent of returned fundscompares with the 500 results he/she could have played. Thus, thepresent invention may offer further enticements to users in that a usercan see what would have happened if he/she had continued playing (ormore generally, performing the activity).

As an aside, note that is an aspect of the present invention thatalthough such ACTIVITY_DATA may be transmitted through a communicationsnetwork, at least some of the software and/or data for the activity maybe provided on a storage media such as a compact disk, or a DVD.Accordingly, it is within the scope of the present invention that thesoftware and/or hardware for enabling embodiments of the presentinvention may be provided from a plurality of different sources.However, in each embodiment of the flowchart of FIG. 2, ACTIVITY_DATA isinfluential in determining one or more of: an outcome for the activity,prizes and/or winnings that can be distributed to users performing theactivity to which the ACTIVITY_DATA is related.

Returning to FIG. 2, in step 212, the prize offering entity waits for auser U to request to participate in the activity (or instance thereof).Subsequently, in step 216, if the user has not previously provided tothe prize offering entity, the public key of a public/private keyencryption pair specific to the user (and likely generated by the user),then the user provides such a public key to the prize offering entity inthis step. Note that in one embodiment of the present flowchart, theuser transmits his/her public key to the prize offering entity via theInternet. In step 220, the prize offering entity encrypts, with theuser's public key, the ACTIVITY_DATA for the (instance of the) activityin which the user has requested to participate. Accordingly, the resultsof this encryption is denoted herein as ENCODED_ACTIVITY_DATA. Thus, itis worth noting that once ACTIVITY_DATA is encrypted intoENCODED_ACTIVITY_DATA, the prize offering entity is restricted frommanipulating this activity related data for purposely changing this datain a predictable way that, e.g., provides the user with either a greaterdisadvantage or advantage than would otherwise be the case if there wereno tampering with such data.

Subsequently, in step 224, the prize offering entity encrypts theENCODED ACTIVITY_DATA with a second encryption procedure using acorresponding secret key, K_(U), not available to the user U (and likelynot available to any user or participant in the activity). Note thatK_(U) may be different for each time the user participates in theactivity. Thus, assuming the second encryption is dependent on K_(u),each such second encryption will be different. Accordingly, the resultis that ACTIVITY_DATA is now doubly encrypted and the results will bedenoted herein as DOUBLY_ENCODED_ACTIVITY_DATA. In step 228, the prizeoffering entity provides DOUBLY_ENCODED_ACTIVITY_DATA to the user U. Inparticular, DOUBLY_ENCODED_ACTIVITY_DATA may be transmitted to the userU via the Internet. Thus, DOUBLY_ENCODED_ACTIVITY_DATA cannot be changedin a predictable way by either the prize offering entity or the user U.Further, as discussed with reference to the winning entries data of FIG.1, if ACTIVITY_DATA is interleaved with random alphanumeric “noise” datain a simple predictable fashion (e.g., prior to encoding ACTIVITY_DATAwith the user's public key, ACTIVITY_DATA is interleaved withmeaningless “noise” data according to, e.g., a formula dependent upon asmall number of parameters (e.g., ≤3), such that users can manually orwith a conventional calculator distinguish the data of ACTIVITY_DATAfrom the noise data once values for the parameters are provided). Thus,with the introduction of noise data, the data encrypted by the user'spublic key (step 220) can be substantially larger than ACTIVITY_DATA.Moreover, since a majority of the data encrypted with the user's publickey may be noise or random data, it is believed that this furtherinhibits illicit access to ACTIVITY_DATA by the user.

Following step 228, the two steps 232 and 236 are performedsubstantially asynchronously, wherein step 232 is performed by the userand step 236 is performed by the prize offering entity substantiallyindependent from step 232. In particular, in step 232, the user Uperforms the (instance of the) activity, and in step 236, adetermination is made by the prize offering entity as to whether otherusers are allowed to participate in the (instance of the) activity.Accordingly, if other users are allowed to participate, then steps 212through 236 are again performed until no further users are allowed toparticipate the (instance of the) activity. After step 232 and/or step236, step 240 is encountered wherein each user participating in theactivity and/or the prize offering entity waits for all users tocomplete the (instance of the) activity. In particular, step 240 may beinterpreted to mean that no further steps for the present flowchart areavailable to be performed until all users have performed the (instanceof the) activity, and the prize offering entity has determined thatthere are no further users eligible to participate in the (instance ofthe) activity. However, step 240 should not be given a narrowinterpretation wherein users and/or the prize offering entitysubstantially ceases to perform other tasks than the steps of thepresent flowchart. For example, if the prize offering entity is awebsite that is providing a tournament for a particular game, whereineach user must complete a predetermined number of game instances, thenone or more users and/or the prize offering entity may be required towait (at step 240) for a plurality of days until all users havecompleted the predetermined number of games, or a tournament time limithas expired. However, this does not mean that the website ceasesperforming tasks substantially unrelated to the final step (244) of FIG.2.

Once all users have completed the (instance of the) activity, then step244 is performed, wherein the prize offering entity provides to at leastone or more of the users U, a corresponding one of the secret keys K_(U)so that each of these users can decrypt DOUBLY_ENCODED_ACTIVITY_DATA,first with K_(U), and subsequently with the user's private key. Thus,the user is able to obtain a copy of ACTIVITY_DATA for determiningwhether this data is consistent with the version of this data used whenthe user was performing (the instance of) the activity. Additionally,note that if ACTIVITY_DATA is interleaved with noise data, then inaddition to the secret key K_(U), the prize offering entity providesthese users with any additional information to select ACTIVITY_DATA fromthe interleaved noise data. Note that for users that are geographicallydispersed from one another and from the prize offering entity such asoccurs in Internet communications, it may be preferable for every user uto receive a corresponding secret key(s) K_(U) so that every user canobtain a copy of ACTIVITY_DATA.

When using the method of FIG. 2 with activities such as the playing of acard game on a communications network, it is a further aspect of thepresent invention that users (i.e., players) may be additionally assuredthat a sequence of card representations are not sequence in a mannerthat results in an unexpected or unfair disadvantage for the user. Inparticular, each user may be allowed to select the next one or more cardrepresentations to be played from the initial card sequence provided bythe prize winning entity. For instance, each user may be allowed tospecify cards to be played by: (a) selecting a subsequence of the cardrepresentations such as every second card (more generally, every n^(th)card), or (b) randomly select the next one or more card representationsby inputting positional information indicating the position(s) of thenext card(s) to be played, such as positional information being, e.g.,numerical input or graphical pointer (mouse) input. Thus, the sequenceof card representations is not predetermined by the prize offeringentity, but the initial sequence of card representations ispredetermined and verifiable by users.

Note that in another embodiment, the present invention may be used as atrustworthy system and method for performing a procedure similar to“drawing straws,” wherein the users (e.g., straw drawers) utilize acommunication network (e.g., the Internet) to draw the “straws,” andwherein the users do not necessarily trust one another. In particular,the present invention allows the users in a group of users to select oneor more of their group randomly (or some particular random option)without an intervening trusted third party.

In a simple version of the present embodiment, a designated user of thegroup generates a list of N distinct numbers (N≥2), wherein N is thenumber of users in the group. Subsequently, each member (other than thedesignated user) supplies the designated user with a public key of apublic/private encryption key pair. For each user supplied public key,the designated user encrypts the list with the public key and thenencrypts the result with a secret key known only to the designated user.The designated user then transmits the doubly encoded list to the userthat supplied the public key. Accordingly, once the designated user hassupplied a doubly encrypted version of the list to each of the otherusers of the group, each user other than the designated user selects adistinct number from the list by, e.g., requesting the number in aparticular position in the list such as the number in the fifthposition. Accordingly, the designated user by default is provided withthe single remaining number after all other users of the group haveselected a number from the list. Then, the designated user supplies eachof the other users with the designated user's secret key so that each ofthe other users can decrypt their doubly encrypted version of the list,first with the designated user's secret key, and then with theircorresponding private key of their public/private encryption key pair.Thus, each user can verify that the list was not manipulated during thenumber selection process, and accordingly, all users can be assured thatthe users selected and/or unselected according to a predeterminedcriteria related to the value of the numbers (e.g., the small number)was performed fairly.

The foregoing discussion of the invention has been presented forpurposes of illustration and description. Further, the description isnot intended to limit the invention to the form disclosed herein.Consequently, variations and modifications commensurate with the aboveteachings, and within the skill and knowledge of the relevant art, arewithin the scope of the present invention. The embodiments describedhereinabove are further intended to explain the best mode presentlyknown of practicing the invention and to enable others skilled in theart to utilize the invention as such, or in other embodiments, and withthe various modifications required by their particular application oruses of the invention. It is intended that the appended claims beconstrued to include alternative embodiments to the extent permitted bythe prior art.

What is claimed is:
 1. A method for restricting access to informationcommunicated between parties, comprising: first encoding of theinformation for obtaining a corresponding first encoded version of theinformation; second encoding said first encoded version for obtaining acorresponding second encoded version of the information; wherein one ofsaid first and second steps of encoding results in said correspondingversion being substantially restricted from a first party decoding theinformation encoded therein without having access to a first decodingdata; wherein another of said first and second steps of encoding resultsin said corresponding version being substantially restricted from asecond party decoding the information therein without having access to asecond decoding data; first providing, to the second party, said secondencoded version; subsequently, performing a predetermined activitybetween the first and second parties using an instance of theinformation, wherein the second party does not have access to saidsecond decoding data but has access to at least portions of theinformation; subsequently, second providing to the second party saidsecond decoding data; wherein the second party decodes the secondencoded version using the second decoding data, and then decodes thefirst encoded version using the first decoding data.
 2. The method asclaimed in claim 1, wherein the first party is a provider of saidpredetermined activity, and the second party is a participant in saidpredetermined activity.
 3. The method, as claimed in claim 2, wherein atleast one of the steps of first providing, second providing andperforming includes communicating between the first and second partiesvia a communications network.
 4. The method, as claimed in claim 3,wherein said communications network includes one or more of: a localarea network, a wide area network, the World Wide Web, and the Internet.5. The method, as claimed in claim 1, wherein said predeterminedactivity includes a game, wherein the information includes an orderedcollection of game token values to be presented to the second party inaccordance with one or more game rules.
 6. The method as claimed inclaim 1, wherein said predetermined activity allows participants toenter the activity and obtain an entry identification, and wherein saidpredetermined activity associates one or more entry identifications withan outcome from said predetermined activity.
 7. The method as claimed inclaim 6, wherein said predetermined activity is one of: a contest, alottery, a drawing, and a sweepstakes.
 8. The method as claimed in claim1, wherein at least one of said steps of first and second encodingincludes encrypting the information using a key from a public/privateencryption key pair.
 9. The method as claimed in claim 9, wherein atleast one of said steps of first and second encoding includes encryptingthe information using a secret key.
 10. The method as claimed in claim1, further including a step of transmitting said first decoding datafrom the second party to the first party via a communications network.11. The method, as claimed in claim 1, wherein said second decoding datais a decryption key.
 12. The method, as claimed in claim 1, furtherincluding a step of comparing said instance of the information with saiddecoded version.
 13. The method of claim 1, wherein one of said steps offirst and second encoding uses one of an RSA encryption technique, a DESencryption technique, and a hashing technique.
 14. The method of claim1, further including a step of obtaining a decoder for performing one ofsaid first and second decoding step from a trusted third party.
 15. Themethod of claim 15, wherein said step of obtaining includes downloadingsaid decoder from an Internet website.
 16. A method for restrictingaccess to information communicated between parties, comprising: firstencoding of the information for obtaining a corresponding first encodedversion of the information; second encoding of said first encodedversion for obtaining a corresponding second encoded version of theinformation; wherein one of said first and second steps of encodingresults in said corresponding version being substantially restrictedfrom a first party manipulating the information encoded therein withouthaving access to a first decoding data; wherein another of said firstand second steps of encoding results in said corresponding version beingsubstantially restricted from a second party determining the informationtherein without having access to a second decoding data; firstproviding, to the second party, said second encoded version;subsequently, performing a predetermined activity between the first andsecond parties using an instance of the information, wherein the secondparty does not have access to said second decoding data but has accessto at least portions of the information; subsequently, second providingto the second party said second decoding data; wherein the second partydecodes the second encoded version using the second decoding data, andthen decodes the first encoded version using the first decoding data.17. A method for verifying network communications between partiesparticipating in one of a game and contest, comprising: activating aninstance of an activity between at least a first party and a secondparty using transmissions on the communications network, wherein saidactivity is one of a contest and a game; first transmitting between athird party and at least one of the first and second parties a firstversion of activity related data for participating in said instance viacommunications on the network; second transmitting, via thecommunications network, one or more portions of a second version of saiddata to said second party from one of said first party and said thirdparty prior to a termination of the instance, wherein said first andsecond versions are expected to be identical by at least one of thefirst party and the second party; requesting, via the communicationsnetwork, by at least one of the first and second parties, that the thirdparty verify that said first and second versions are identical.